System and method for providing end-to-end quality of service (QoS) across multiple internet protocol (IP) networks

Abstract

A system and method of ensuring a requested Quality of Service (QoS) for a media flow that is transported through multiple transport networks. An interface is established between a Call State Control Function (P-CSCF) and a Bandwidth Broker (BB) for the passing of a session description and Binding Information from the P-CSCF to the BB. The interface uses the Common Open Policy Service (COPS) protocol and the Bandwidth Broker (BB) protocol. The Binding Information may be the source IP address plus Real Time Protocol (RTP) port and the destination IP address plus RTP port. The Binding Information is also passed back toward the Originating BB (BB-O) from a Serving BB (BB-S) in the terminating (serving) network through BBs in adjacent networks using the BB protocol.

What is claimed is:  
     
         1 . A method of ensuring a requested Quality of Service (QoS) for a media flow that is routed from a first terminal in an originating network, through at least one transit network, to a second terminal in a terminating network, said originating network including an Originating Bandwidth Broker (BB-O) and an Originating Media Policy Server (MPS-O), said transit network including a Transit Bandwidth Broker (BB-T) and a Transit Media Policy Server (MPS-T), and said terminating network including a Serving Bandwidth Broker (BB-S) and a Serving Media Policy Server (MPS-S), said method comprising the steps of: 
 sending an origination message from the originating network to the terminating network with a proposed session description that identifies the requested QoS;    determining by the terminating network that the session description is agreeable;    sending a first Bandwidth Broker Protocol Resource Allocation Request (RAR) from the BB-S to the BB-T with binding information that identifies the first and second terminals and the requested QoS;    determining by the BB-T whether a Service Level Agreement (SLA) between the transit network and the terminating network allows sufficient resources to be allocated to meet the requested QoS;    sending a second RAR from the BB-T to the BB-O with the binding information, upon determining by the BB-T that the SLA between the transit network and the terminating network allows sufficient resources to be allocated to meet the requested QoS;    reserving the resources required to meet the requested QoS in the originating network, the transit network, and the terminating network; and    setting up a multimedia session to carry the media flow with the requested QoS.    
     
     
         2 . The method of ensuring a requested QoS for a media flow of  claim 1  further comprising, after the step of sending a second RAR from the BB-T to the BB-O with the binding information, the steps of: 
 sending a first Resource Allocation Answer (RAA) from the BB-O to the BB-T;  
 sending a second RAA from the BB-T to the BB-S; and  
 installing by the BB-O, the BB-T, and the BB-S, applicable policies in edge routers to provide the requested QoS in the originating network, the transit network, and the terminating network, respectively.  
 
     
     
         3 . The method of ensuring a requested QoS for a media flow of  claim 2  further comprising, before the step of reserving the resources required to meet the requested QoS, the steps of: 
 sending a QoS reservation request that includes the agreed session description and the binding information from an Originating Call State Control Function (Originating P-CSCF) to the BB-O;  
 determining by the BB-O whether a previous valid resource reservation exists for the session associated with the binding information; and  
 sending an immediate successful reservation response from the BB-O to the Originating P-CSCF, upon determining that a previous valid resource reservation exists for the session associated with the binding information.  
 
     
     
         4 . The method of ensuring a requested QoS f or a media flow of  claim 3  further comprising the steps of: 
 reserving resources required for the requested QoS, upon determining that a previous valid resource reservation does not exist for the session associated with the binding information.  
 
     
     
         5 . The method of ensuring a requested QoS for a media flow of  claim 4  wherein the step of determining by the BB-O whether a previous valid resource reservation exists includes the steps of: 
 determining whether a previous resource reservation was made for the session associated with the binding information; and  
 upon determining that a previous resource reservation was made, determining from a time stamp associated with the previous reservation whether the previous reservation is still valid.  
 
     
     
         6 . The method of ensuring a requested QoS for a media flow of  claim 3  wherein the step of sending the QoS reservation request from the Originating P-CSCF to the BB-O includes sending the QoS reservation request utilizing a Common Open Policy Service (COPS) protocol and a Bandwidth Broker protocol.  
     
     
         7 . The method of ensuring a requested QoS for a media flow of  claim 1  further comprising the step of creating the binding information from a source Internet Protocol (IP) address of the first terminal, an identification of a Real Time Protocol (RTP) port assigned by the first terminal, a destination IP address of the second terminal, and an identification of an RTP port assigned by the second terminal.  
     
     
         8 . A Multimedia Control Server (MMCS) in a multi-service core network for ensuring a requested Quality of Service (QoS) for a media flow being routed from a first terminal in the core network to a second terminal in a terminating network, said MMCS comprising: 
 an Originating Call State Control Function (Originating P-CSCF) that serves the first terminal;    an Originating Bandwidth Broker (BB-O) that manages resources in the originating network;    a first interface between the Originating P-CSCF and the BB-O for passing binding information from the Originating P-CSCF to the BB-O, the binding information identifying the first and second terminals and the requested QoS;    an Originating Media Policy Server (MPS-O) that provides policy rules regarding allocation of resources in the originating network;    a second interface between the MPS-O and the BB-O for passing the policy rules from the MPS-O to the BB-O; and    a third interface between the BB-O and a plurality of edge routers that route the media flow into and out of the originating network, said third interface for passing from the BB-O to the edge routers, policy rules applicable to a specific media flow.    
     
     
         9 . A Multimedia Control Server (MMCS) in a multi-service core network for ensuring a requested Quality of Service (QoS) for a media flow from an application on a first terminal that is transported through a network owned by an administration, said media flow being routed through at least one transit network that is not owned by the same administration, to a second terminal in a terminating network, said MMCS comprising: 
 an Originating Call State Control Function (Originating P-CSCF) that serves the first terminal;    an Originating Bandwidth Broker (BB-O) that manages resources in the originating network;    a first interface between the Originating P-CSCF and the BB-O for passing a session description and binding information from the Originating P-CSCF to the BB-O, the binding information identifying the first and second terminals and the requested QoS;    an Originating Media Policy Server (MPS-O) that provides policy rules regarding allocation of resources in the originating network;    a second interface between the MPS-O and the BB-O for passing the policy rules from the MPS-O to the BB-O;    a third interface between the BB-O and a plurality of edge routers that route the media flow into and out of the originating network, said third interface for passing from the BB-O to the edge routers, policy rules applicable to a specific media flow; and    a fourth interface between the BB-O and a Transit Bandwidth Broker (BB-T) in the transit network for passing the binding information from the BB-T to the BB-O, said binding information having been received by the BB-T from a Serving Bandwidth Broker (BB-S) in the terminating network.    
     
     
         10 . The MMCS of  claim 9  further comprising a fifth interface between the MPS-O and a clearing house that performs as an Authorization, Authentication, and Accounting (AAA) server.  
     
     
         11 . A system for ensuring a requested Quality of Service (QoS) for a media flow belonging to an application and originating in an originating network owned by an administration, said media flow being routed from a first terminal in the originating network through at least one transit network that is not owned by the same administration, to a second terminal in a terminating network, said system comprising: 
 a first Multimedia Control Server (MMCS) in the originating network comprising: 
 an Originating Call State Control Function (Originating P-CSCF) that serves the first terminal;  
 an Originating Bandwidth Broker (BB-O) that manages resources in the originating network;  
 a first interface between the Originating P-CSCF and the BB-O for passing a session description and binding information from the Originating P-CSCF to the BB-O, the binding information identifying the first and second terminals and the requested QoS;  
 an Originating Media Policy Server (MPS-O) that provides policy rules regarding allocation of resources in the originating network;  
 a second interface between the MPS-O and the BB-O for passing the policy rules to the BB-O;  
   a plurality of originating edge routers that route the media flow into and out of the originating network;    a third interface between the originating edge routers and the BB-O for passing policy rules applicable to specific media flows from the BB-O to the originating edge routers;    a second MMCS in the terminating network comprising: 
 a Serving Call State Control Function (Terminating P-CSCF) that serves the second terminal;  
 a Serving Bandwidth Broker (BB-S) that manages resources in the terminating network;  
 a fourth interface between the Terminating P-CSCF and the BB-S for passing an agreed session description from the Terminating P-CSCF to the BB-S;  
 a Serving Media Policy Server (MPS-S) that provides policy rules regarding allocation of resources in the terminating network;  
 a fifth interface between the MPS-S and the BB-S for passing the policy rules from the MPS-S to the BB-S;  
   a plurality of serving edge routers that route the media flow into and out of the terminating network;    a sixth interface between the serving edge routers and the BB-S for passing policy rules applicable to specific media flows from the BB-S to the serving edge routers;    a Transit Bandwidth Broker (BB-T) in the transit network;    a seventh interface between the BB-S and the BB-T for passing the binding information from the BB-S to the BB-T in a first Resource Allocation Request (RAR); and    an eighth interface between the BB-T and the BB-O for passing the binding information from the BB-T to the BB-O in a second RAR.